Abstract

Insect play a significant role limits crop production. For their control, most of the farmers used chemical pesticides which have
adverse impact on environment and human health. In India, insecticides are used a large amount than other pesticides such as
fungicides and herbicides. Conventional insecticides acquire inherent toxicities that jeopardize to the environment and also effect
on human beings and other living organisms. Negative effects of conventional insecticides on human health led to a resurgence in
interest in botanical insecticides because of their minimal ecological side effects and save for exploit. To solve these problems there
is need a modern concept of pest management based upon an understanding of agroecosystem ecology, and integration of various
control tactics into pest management systems. IPM is a tactics pest management including monitoring of insect populations, cultural,
mechanical, biological and chemical methods of insect-pest’s management. In all several IPM tactics there is biological pests control
are useful technique that discourage the development of populations of harmful organisms. The manipulation of beneficial organisms
or natural enemies remains a very important tool in integrated pest management program of insect-pests all over the world. In
the present studies have descried implement biological control tactics which act useful tactic in IPM. It also explains how biological
control interacts with other IPM tactics. Biological control, i.e. natural enemies, has been accepted as an effective, environmentally
non-degrading, technically appropriate, economically viable and socially acceptable method of pest management.

Keywords: IPM; Pesticides; Biological Control; Management

Introduction

Last 50 years farmers adopted broad-spectrum conventional insecticides
such as organochlorines, organophosphates, carbamates
and pyrethroids based pest control tactic. However, the chemical
pesticide has adverse effects of on the environment, problems of
resistance and resurgence reaching crisis proportions [1]. To reduce
the use of synthetic pesticides in crop protection to need alternative
and novel methods for pest control as IPM. Biological control
has been a precious approach in pest management approaches
around the world for long years. Biological control is the process to
use of a living organism to reduce the population density of another
organism (Jonsson., et al. 2008). There are main principles of biological
control. Biological control tactics maneuver throughout the
world as part of the management of pests in agriculture, forestry
and horticultural crops. Although biological control has sometimes
been commenced to combat arthropod pests that encompass developed
resistance to insecticides. In the present status of increase
population there is need to increase food production from the
reducing agricultural land. To fulfil these objective farmers used
chemical pesticides to reduce completions with insect-pests [2].

Due to over-reliance on chemical control, with the well-described
consequences of pest resistance, uneconomic production costs,
bioaccumulation through food chains, environmental pollution,
loss of biodiversity and risks for human health. In the present review
article, we also discuss about contribute of biological control
to sustainable agriculture, increase biodiversity and limitations of
biological control in integrated pest management.

Approach to Biological Control

Biological control agents have been utilizing in the management
of insect-pests for long time in the different parts of the world.
However, in last 3 - 4 decades have seen a dramatic increase in
their use after the recognized some drawback of conventional pesticides
against environment and human benign. After this incident
farmers as well as police makers create an interest to understanding
how they can better be manipulated as part of effective, safe,
pest Management systems (Clark, 2007) are revealing surprising
complexities in the life histories of these organisms. Although the
long history of utilizing natural enemies, it wasn’t until 1919 that
the term biological control was it appears that used for the first time by the late Harry Smith of the University of California [3].

Tools of biological control

There are several living organisms are used to insect-pest’s management
as biological control agents. Biological control can also be
defined as the utilization of natural enemies to reduce the damage
caused by noxious organisms to tolerable levels. Biological control
is often shortened to biocontrol.

Examples of biocontrol include the use of lady bugs to prey on
aphids and scale insects and treatment of turf with spores of the
bacterium Bacillus popilliae, which cause milky disease in Japanese
beetle larvae.

Natural enemies of insect pests, also known as biological control
agents, include predators, parasitoids, and pathogens. Biological
control agents of plant diseases are most often referred to as antagonists.
Biological control agents of weeds include seed predators,
herbivores and plant pathogens.

Predator

A predator is an animal that depends on predation for its food.
In other words, predators sustain life by killing and consuming
animals of other species. The predatory behaviour is widespread
among insects, spiders and mites. There are more than 40 families
of insect predators that are significant for pest suppression in agriculture
and forestry of these, the Anthocoridae, Pentatomidae,
Reduviidae, Carabidae, Coccinellidae, Staphylinidae, Chrysopidae,
Cecidomyiidae, Syrphidae, Formicidae, Gerridae, Miridae, Vellidae
and Dytiscidae are most commonly found preying on pest species
in crop fields. Virtually all members of all the 60 families of spiders
(Araneda) are predators. Vertebrate predators that attack insect
pests include birds, small mammals (bats), lizards, amphibians
(frogs and toads), and fishes.

Parasite

A parasite is an organism living in or on another living organism,
obtaining nutrients from their host, resulting altered growth, development
and reproduction or death for the host. Approximately
10% of all insect species can be classified as parasitoids. The main
difference between parasites and parasitoids is that parasites may
not kill their hosts but parasitoids do. About 75% of the parasitoids
are Hymenoptera; the remaining 25% is composed of Diptera,
Strepsiptera, Neuroptera, Coleoptera and Lepidoptera.

Members of 43 families of the order Hymenoptera are parasitoids.
Twelve families of Diptera contain some species whose larvae
are parasitoids of arthropods and snails. 26 families of parasitoids
have been used in biological control. The most frequently
used groups in the Hymenoptera are Braconidae, Ichneumonidae,
Eulophidae, Pteromalidae, Encrytidae and Aphelinidae. Some
parasitoids are also found in the insect order Strepsiptera, Lepidoptera
and Coleoptera, although parasitism is not typical of the
Lepidoptera and Coleoptera.

Pathogens are diseases that attack pest insects. Pathogens of
agricultural pests are usually bacterial, fungal or viral. A large
range of micro-organisms such as bacteria, viruses, fungi and protozoans
have since been identified as potential candidates for use
in biocontrol strategies against insect pests [4].

Bacteria

Most of the pathogenic entobacteria are comes under the family’s
Bacillaceae, Pseudomonadaceae, Enterobacteriaceae, Streptococcaceae,
and Micrococaceae [5]. There is much diverse kind of
bacteria that are identified to acutely or chronically infect insects,
but only members of two genera of the order have ever been registered
to control insects i.e. Eubacteriales, Bacillus (Bacillaceae)
and Serratia (Enterobacteriaceae). Bacillus is through far the most
significant microbial pesticide genus. The species of the Bacillaceae,
Bacillus thuringiensis (B. t.), has been the most widely used and
successful microbial pesticide. There are several important subspecies
of B.t. that have been registered and marketed as separate
products on different insect pests. These include Bacillus thuringiensis
subsp. aizawai (B.t.a) for control of other Lepidoptera less
susceptible to B.t.k., Bacillus thuringiensis subsp. Israelensis for
control of mosquitoes and blackflies, and Bacillus thuringiensis
subsp. Tenebrionis for control of leaf beetles in the family Chrysomelidae.

Virus

The first accounts of baculovirus infections come from diseased
silkworms in ancient China [6].

It was also during this time that the large nuclear polyhedrosis
viruses (NPVs) were distinguished from the much smaller granular
looking viruses (i.e., granulosis viruses (GVs)). Bergold was the
first to characterize the rod-shaped virions found within the occlusion
bodies in the 1930s and 1940s.

It was also during this time that the utility of baculoviruses as
biocontrol agents was described [6]. Viruses have been isolated
from more than a thousand species of insects from at least 13 different
insect orders [5].

Entomopathogenic viruses from almost a dozen viral families
have been isolated: Ascoviridae, Baculoviridae, Birnaviridae, Iridoviridae,
Nodaviridae, Parvoviridae, Picornaviridae, Poxviridae,
Reoviridae, Rhabdoviridae, and Tetraviridae [7,8]. But the Baculoviruses
i. e. family currently consists of two genera, the Nucleopolyhedroviruses
(NPVs) and Granuloviruses (GVs). These new genera
replace the Nuclear Polyhedrosis Viruses (Subgenus A) and Granulosis
Viruses (Subgenus B), respectively.

Fungus

As with the bacteria, the diversity of fungi known to infect insects
is great. Entomopathogenic fungi are found in the division
Eumycota in the subdivisions: Mastigomycotina, Zygomycotina,
Ascomycotina, and Deuteromycotina [9]. The two most important
orders are the Entomophthorales (Zygomycotina: Zygomycetes)
and the Moniliales (Deuteromycotina: Hyphomycetes syn. Deuteromycetes).

Recently there has been a move to reclassify the imperfect fungi
(i.e., Deuteromycotina) as mitosporitic fungi because their sexual
stages are unknown or no longer exist and they cannot be effectively
classified.

Unlike the bacteria and viruses, which must be consumed, toxicity
from entomopathogenic fungi most often occurs from contact of
the fungal conidia with the host cuticle. This necessitates thorough
coverage of the pests and foliage. Currently, the most widely used
fungal insecticide is Beauveria bassiana. There are currently two
registered fungal insecticides in the genus Metarhizium. M. anisopliae
was one of the first fungi used in biological control experiments.
Production of the Deuteromycetes is much less expensive [10].

They have a much broader host range and are able to grow and
sporulate on many generalized media. They can adapt to a wide
variety of growing conditions. This has made them the fungi most
amenable to mass production. For descriptions of mass production
of B. bassiana, B. brongiartii, M. anisopliae, and P.

Conclusion

The use of biological control in pest management systems has a
long and rich history. While there is a variety of obstruction, there
are so many opportunities for them to use as natural enemies in the
management of insect-pests. Biological pest management tactics
are important due to environmental and human safety concerns,
development of insecticide-resistance, increases in pesticide cost
etc. However, pesticides will likely remain a major component of IPM programs into the foreseeable future. Medications of pesticide
use practices will also probably remain the most commonly
implemented form of biological control in agricultural IPM. As IPM
develop more ecologically based practice. Global climate change is
beginning to affect agricultural systems worldwide and biological
control practices may have to alter to adapt to these changes. Recent
losses of conservation land and increased use of genetically
modified crops and rising demand for organic produce IPM will
have an important role to play, and the use of biological controls
can be an integral part of IPM.